as you unlock more technologies, it becomes increasingly easy to refactor/maintain a large factory. ex: bots are a major inflection point in the game. you could scale up petroleum processing and red circuits before getting bots (you need these two things to make them), but that involves a lot of manual effort. it's usually better to do a barely sufficient (but tileable!) petroleum and rc setup, then immediately fix it after making a few construction bots.
more general tip: clean interfaces are more important than massive capacity up front. in the long run, you will always need more steel/circuits/etc than you can serve with a single production line. but even if the internal layout is a mess, a functional unit with a clean interface can be scaled horizontally forever.
Cleanliness doesn't really matter, because space is infinite.
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So long as you've unlocked enough military (ie: shotgun in the early game, or tank in the mid-game), you can just clear out more room and then build there. (Shotgun has significant pierce-damage, enough to kill the alien bases. Tank also has significant pierce damage and impact-damage, allowing you to win against small / medium aliens through the midgame rather easily and cheaply)
Don't even "tear down" your oldbase. Just fully abandon it and move elsewhere. Even without bots, there's no penalty to "just leaving".
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Bots / deconstruction planner is more of a thing if you're tired of cleaning out biter-territory and want to "recycle" your old areas.
Hi, it's me your local site reliability engineer. I care about things like latency, monitoring, and being able to understand the overall moving pieces. Scaling things in appropriate ratios is also relevant to me. I'd put you in a storage box and nuke if I could, but let's go have this conversation standing on these train tracks.
Good luck bootstrapping your first Kovarex U235 units!
A properly done Kovarex U235 takes about 2-hours to bootstrap itself. By this point in the game, you need to be able to "predict" how the factory will work in 2+ hours of latency and make sure things work as expected. (Or I guess you can blueprint copy/paste from an internet forum... but I find that "my own designs" are what make Factorio fun)
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Once you're able to "predict" how the factory works in 2, 3, 4 hour scales, a lot of good designs open up. You focus on throughput and *eventual* designs... willing to wait 3 hours to get things done.
And by "wait", I mean go play somewhere else for those 2 hours. There's always more work to do, a design that takes 3 hours to complete _AUTOMATICALLY_, but only 5 minutes of manual / human input is superior to a design that takes 10-minutes of human effort but completes in 15 minutes.
The #1 resource in Factorio is player-attention. You should be laying out designs, and then _LEAVING_ in most situations. You let the bots complete the area and come back to "verify" when they're done.
maybe we are talking past each other, but I'd say clean interfaces and bots are very important even if you don't want to tear down the original factory. you want to be able to double production of high volume products with a couple copy-pastes. can't really do this if you have some gnarly IO setup.
I agree clean layouts inside of functional units is unnecessary. land is cheap; just make something that works and cp it everywhere.
> you want to be able to double production of high volume products with a couple copy-pastes.
In my experience, no.
Any high-volume production needs to be built from the ground up from smelters (or even miners) on downwards.
If you have 1-belts of iron feeding your factory and then want to expand, the easiest way to do so is to build a parallel +1 belt of iron (including the 70+ smelters and 50+ miners somewhere else) somewhere.
The terrain and issues of that other area (ie: water, cliffs, trees, etc. etc.) will be different. You can only legitimately "copy/paste" designs if you have an advanced set of terrain modifiers: landfill to erase water, cliff-explosives to erase cliffs, and flamethrowers to erase trees. (Chopping by hand takes too long. Even bots take too long in many situations to erase trees, especially at low-bot speed levels).
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If you try to "logically" add it to your factory (originally designed for only 1-belt), you end up with non-obvious starvation points everywhere.
Its far easier to declare the entire "logical belt" region to be a cohesive design (from mines to smelter to assembly machines to science to labs: beginning to end of the entire process).
There's an additional bonus to this: belting the "end-product sciences" is very easy and low-throughput. Instead of "moving your factory" around, it makes far more sense to "move your science belts" around.
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Its very hard to turn a "1-belt of iron + 1-belt of copper" factory into a "2-belt of iron + 2-belt of copper". Very very difficult, you really shouldn't be trying to find space for the extra belt or smelters.
Just "soft abandon" the base, and build your 2nd belt of iron + 2nd belt of copper elsewhere. Then build 2-belts of your red+green+blue+purple science (or whatever outputs your old base were doing) to lead to the new science center. "Abandon" the old science center as well (since the "old science" center won't have the extra science to advance forward).
"Abandoning" the science center means that all that space opens up for you to move your science-belts to the necessary location towards the new science center. Maybe you need to plow through some old areas but it'd be easier to do this from an "abandonment" mindset rather than a "cleanup" mindset.
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The only way you "cleanly" have room for that 2nd line of copper or iron, is if you magically remembered to leave room for the 70-smelters before you built the base. This is unreasonable.
EDIT: I guess you use yellow/red belts in the early game. 24-smelters per yellow belt of production. 48-smelters per red belt of production. 72-smelters per blue belt of production.
How do you grow 24-furnaces into 48? Doubling the size if you upgrade from yellow to red? (Or upgrading from 1x yellow to 2x yellow?). Its non-trivial to run that many lines through the middle of already-built factory areas.
And unless you planned for it, 24-additional furnaces is a non-trivial amount of space.
before I have bots, I usually put down a minimal production line that doesn't saturation a belt. I place them perpendicular to the main bus, so they can be 2x'd or 4x'd before saturating an output belt or fully consuming an input. in the early stages of having bots, I scale them a couple times as needed.
but once I have a good number of bots and a couple speed upgrades for them, I try to switch to remote train-served factories for bulk items. so doubling steel really is as simple as copypasting the original smelters and train stops. with current train mechanics, you don't even have to rename the stops. from here you can either fully transition to block architecture (probably overkill for vanilla) or widen your original bus at the end by injecting materials via train.
if you do it right, the only manual effort for scaling is adding new trains to prevent starvation.
It sounds like you're inadvertently benefiting from an advanced concept called "compression".
A yellow iron-belt can send at most, 15-iron per second, towards the factory. The player can spend this on 3-steel per second, 15-green circuits per second, 7.5 gears per second, or any such combination of intermediate materials.
However, "steel" has an interesting property, every "1 steel" you send down the factory is equivalent to sending 5-iron down to the factory.
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This means that your singular steel belt sending only a partial belt (maybe 6-steel/second, which is only 40% capacity) is "equivalent" to sending 2-iron belts (30-iron per second).
"Compression" means that you only have to think about running 40% belt of steel, rather than 2x 100% belts of iron. This takes up 1/2 the space and is far simpler in the overall picture, and even leaves room on the belt for up to 2.5x expansion later. (Your 40% yellow belt can "expand" to 100% capacity in the long-game, ultimately reaching the same throughput as 5x yellow belts of iron at 100% capacity).
Playing with "compression" can lead to simplified designs. Similarly, green-circuits are great at compression (1-iron + 1.5 copper per circuit), as are gears (1-gear == 2-iron). But steel is among the best (5-iron per steel).
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If you work at the "steel" level and plan around a "future steel belt", you end up benefiting from compression and leading yourself towards simpler designs.
But that's an advanced concept. This isn't something I'd expect a beginner or intermediate Factorio player to get. The beginner/intermediate player would try to brute force the additional iron-lines using iron plates directly, and have a difficult job of doing so. It takes multiple playthroughs before you realize that belting-steel has benefits over belting-iron from a factory throughput perspective.
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The recommendation I put above, to belt your science to new locations, is the ultimate answer to this compression. A blue-science pack consists of 1.5x adv. circuit + 1x engine + .5x sulfur
That is to say: one blue-science pack is 7.5 copper + 12 iron + 3 plastic + 1/2 sulfur, or roughly 23-resources per blue-science pack. That's a compression ratio of 23-to-1, superior to steel.
This makes "belting" blue science around a relatively efficient endeavor from a human-labor perspective. (True: the factory has to work 23x harder to "fill the belt", but if we're talking about "eventual consistency" measured in the scope of hours, its not really that big of a deal to wait for the belt of science-packs to fill up to its steady state level.
And by "wait", I mean, "play the other elements of factorio while waiting". I know its going to take 3 or 4 hours to happen, but I know it will happen with 100% certainty because I have confidence in the design. So I do it, and move on to base expansion / building more train outposts or other manually-intensive jobs.
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In any case, "just expand steel" turns out to be one of the easier tasks. I don't know if you knew steel was specifically a high-compression item worthy of attention like this, but... that's an explicit strategy. One that took me many, many playthroughs to understand and take advantage of.
Usually we fix that with trains, and in some of our last games we started working on pull (or Toyota) model of resource management, with smelting blocks colocated with metal patches, and various sub-factories pulling resources in by signal-triggered trains
I guess I'm talking about the earlier game, where I've seen many, many players 'get stuck at blue science'.
A lot of players get stuck there because you need to advance to the 2nd iron patch around then, because the starter patch is too small to sustain red circuit production.
Or I guess you can wait like 10 hours for that small patch to make enough red circuits.
But yes, a well designed train network solves the problem. But that's a nonobvious step for many players.
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Main bus style does work through that stage of the game, but requires preplanning.
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If you wish to keep your old design (aka: no restarts), building a 2nd base and connecting the two bases up (either with trains or belts) really is the answer.
In any case, the game's default settings force you to expand in the blue to purple science period, before all options of the tech tree are available.
more general tip: clean interfaces are more important than massive capacity up front. in the long run, you will always need more steel/circuits/etc than you can serve with a single production line. but even if the internal layout is a mess, a functional unit with a clean interface can be scaled horizontally forever.